Thermostatic wax pot



Jan. 21, 1936. 5 Dow 2,028,535

THERMOSTAT I C WAX POT Original Filed Nov. 16, 1929 Patented Jan. 21,1936 THERMOSTATIC' WAX POT Harry E. Dow, Beverly, Mass., assignor toUnited Shoe Machinery Corporation, Paterson, N. J., a corporation of NewJersey Original application November 16, 1929, Serial Divided and thisapplication 00- tober 4, 1933, Serial No. 692,119

6 Claims.

The present invention has relation to wax pots, such as are used inconnection with wax thread sewing machines for impregnating the threadwith liquid wax just prior to the incorporation of the thread in theseam being formed by the sewing machine. more particularly to wax potswherein the wax is maintained in molten condition and at a propertemperature for thoroughly permeating the thread by means of electricalheating devices.

The invention has as its object the provision of a novel and. improvedwax pot having advantages over prior constructions through providing areceptacle for the wax which shall be quickly and easily removable fromits supporting means, leaving behind and without disturbing the threadguiding and stripping devices so that it may be entirely separated fromthe rest of the wax pot for the cleaning-out that is necessary atfrequent intervals, and also so that easy access may be had, withoutsoiling the operators fingers, to the thread guide which leads thethread into and through the liquid wax.

To these ends, the invention consists in a wax pot having a supportingbracket, a receptacle for the Wax supported thereby with capacity foreasy removal, and the provision therein of novel and. improved means foreffecting and regulating the stripping of the excess wax from the threadas it is drawn out of the liquid wax. The manner in which this isaccomplished, as well as other features of the invention and theiradvantages, and the means whereby they are attained, will be apparent tothose skilled in the art from the following description and the claimsappended hereto taken in connection with the accompanying drawingshowing the illustrated embodiment of the invention in its preferredform.

In the drawing, Fig. 1 is an elevation and Fig. 2 a plan of the improvedwax pot; Fig. 3. is a side View of the head of the bracket with thereceptacle for the wax and its cover removed, showing the thread guidingand stripping means; Fig. 4 is a partial plan view, in section on line4-4 of Fig. 1, looking in the direction of the arrow; and Fig. 5 is aperspective view of one of the spring-blades of the stripping devices.

The improved wax pot is designed to be mounted in appropriate positionupon the pedestal or other portion of the frame of a wax thread sewingmachine by means of a bracket 2 provided with eyes 4 through whichattaching The invention relates screws 6 may extend into such pedestalor framework. The bracket 2 is formed of aluminum, as are all the othermain parts entering into the construction of the wax pot, in order tosecure maximum diffusion of heat. A bore 8 is formed within the centerof the relatively thick bracket to receive an electric heating unit ofwell known cylindrical shape and familiar construction. This heatingunit is controlled by a thermostat of well known type adapted tointerrupt or reinstate the flow of electrical current according to thechanges of its temperature, and is mounted within an appropriatecup-shaped housing It) formed upon one face of the bracket 2. Thethermostat and its connections are enclosed and protected by a cover [2whichis secured to the bracket by means of a screw M.

The wax is put into a receptacle I6 also of aluminum, which is fitted tothe opposite surface of the bracket 2 by means of a dove-tailedtongue-and-groove joint, the tongue being formed as indicated at i8,upon the material of the side of the bracket closelyadjacent the bore 8within which is the heating unit. The corresponding groove is formed inthe material of the receptacle l6 and the adjoining surface of both thebracket and the receptacle are machined to fit closely against eachother at and about the tongue so that there will be efficient transferof heat from the bracket to the material of the receptacle, to heat thelatter and melt the wax placed therein. While permitting free transferof heating across the joint from the bracket to the receptacle, the fitis such as to permit easy sliding movement of the receptacle up intoworking position along the tongue l8, and down and off from the bracketto permit removal of the receptacle for cleaning. The construction is!such that dirt and other foreign matter will not accumulate and preventthe receptacle entering into close heat-transmitting contact with thebracket. The receptacle is maintained in working relation with thebracket by means of a catch formed by a bolt 20 mounted in an extension22 from the receptacle l8 and pressed by a spring 25 into a recess inthe edge of the bracket, the bolt registering with the recess when thereceptacle has been slid upward into proper position. A knob 26 upon thebolt facilitates its manipulation when it is to be withdrawn to permitlowering or removal of the receptacle for the wax.

The thread guiding and stripping means are mounted upona flange 28depending from a horizontal head enclosure member or cover 30 that ismounted transversely on top of the bracket 2 by means of screws. 32.Thus the thread guiding and stripping means are separate from thereceptacle !6 for the wax, and are not disturbed or moved when thereceptacle is lowered or removed. Provision is made for waxing both theneedle and the bobbin thread, the former passing into the wax potthrough an eye 34 in the head 30, and through a guide 36 standing belowthe level of the melted wax in the receptacle 86 when the latter isadequately filled and in working position, said guide being affixed tothe lower end of the flange 28 by a strap 38 and screw 46. Thence theneedle thread passes upwardly through a scraper 42 and between a springblade 44 and an eccentrically grooved pin 46 which cooperate to effectthe main stripping action, and emerges through the notch 43 in the edgeof the head 36. The bobbin thread is passed through the dry-threadtension 50, of well known design, entering the wax pot through the eye52 in the head 3%, passing down and through a guide eye 5 t similar toguide eye 36 in all respects, and returning through scraping andstripping means 42, 44, 46, similar to those just described and emergingthrough the notch 56 in the edge of the head 30, thence passing over thetruck 58 to the bobbin winding devices, (not shown).

The stripping means have novel features. The eccentrically grooved pins46 are rotatably mounted in the head 36 and have portions of theirlength fluted or toothed as indicated at 66. Cooperating with eachfluted portion is a thumb screw 62 extending at right angles to therespective pin and having its threads 64 engaging with the fluted ortoothed portions 60 of the pin after the manner of a worm and gear, sothat rotation of the thumb screw serves to impart a rotation to thecorresponding pin 46. This arrangement facilitates adjustment of thestripping action effected by the eccentric notches, indicated at 66, inthe end of the pins, the adjustment being effected from the top of thewax pot instead of from within or from a side to which other parts ofthe sewing machine may bar access. Further, either stripping pin 46 maybe easily rotated a complete turn whenever necessary to remove wax cakedthereon and interfering with the stripping action. The thumb screws 62are retained in place by means of collars 63 which are secured byclamping screws 70 upon the reduced extremities which extend out fromthe under side of the material of the head 36. The stripping pins 46 areeach provided with duplicate eccentric grooves 66, so that as one groovewears, the pin may be moved endwise to put the other of such grooves inoperation. Each pin is held against endwise movement, so as to keep itsstripping groove in proper relation with its coacting spring blade 44,by means of a screw i2. threaded into the head 36, so that its reducedextremity enters a groove F4 cut in the pin, a duplicate groove 16 beingformed in proper position to align the alternative eccentric strippinggroove 66 with the spring blade 44 when it is necessary to shift the pinlengthwise.

The spring blade 44 which presses the thread against the fixed surfaceconstituted by the pin 46 has its upper extremity split to form threeseparate spring-fingers, the central one of which registers with theeccentric stripping groove in the pin 46, while the other two bearagainst the surface of the pin at each side of such groove. By thisarrangement, a thread drawn upwardly from the molten wax beneath thecentral finger of the spring blade 44 will be prevented from escapingsidewise from between the pin and the spring blade in the event that aknot or other enlargement on the thread be drawn through the stripper,as the outer pair of fingers press closely against the surface of thepin 46 and act as guides preventing lateral deviation of the threadalong the surface and lengthwise of the pin. This stripping arrangementis easily and quickly threaded up, and through retaining its hold on thethread in spite of knots, etc., prevents the annoyance of having thethread-handling parts become fouled by the action of an unstrippedthread. The spring blade 44 and the scraper 42 are formed integrally ofa single piece of bent spring steel, a portion of which is bent at rightangles to form the attaching bracket 18 which is attached by a screw 86to the flange 2B.

A removable cover 82 is hinged at 84 to lugs 86 upon the head 30, andserves to exclude dirt and to give easy access to the receptacle [6 forthe replenishment of the supply of wax.

It will be apparent that the receptacle [6 containing the wax may beeasily and quickly re- .moved for cleaning or for the purpose ofthreading-up the wax pot by pulling out the bolt 20 and sliding thereceptacle downward along and off from the tongue l8 of the bracket. Inthis manoeuvre no other part of the wax pot is moved, adjusted, ordisturbed. The wax receptacle It may be replaced easily and rapidly bythe single reversal of this procedure.

The present application is a division of Ser. No. 407,668, filedNovember 16, 1929 upon which Patent No. 1,962,007 issued June 5, 1934.

Having thus described the invention, what is claimed is:

1. A wax pot having, in combination, a receptacle for the wax and astripper comprising a fixed surface and a spring blade cooperatingtherewith to wipe wax from a thread passed be tween, the acting end ofthe blade being split into three fingers, the central one of whichpresses the thread against the fixed surface while the outer onesprevent lateral escape of the thread.

2. A wax. pot having, in combination, a receptacle for the wax and astripper comprising a fixed surface and three fingers springpressedthereagainst and closely adjacent each other, the central one pressingthe thread against the fixed surface to remove surplus wax while theother two prevent lateral escape of the thread.

3. A wax pot having, in combination, a receptacle for the wax andthread-stripping means comprising a rotatably mounted pin, means forrotating such pin, an eccentric stripping groove in the pin, and threespring presser-fingers, the central one thereof pressing the thread intothe stripping groove, and the outer ones preventing lateral escape ofthe thread.

4. A wax pot having, in combination, a receptacle for the wax, and athread-stripper comprising a spring presser blade and a rotatablymounted pin having a worm-gear, a worm engaging such gear and adapted tobe rotated to turn the pin, and a plurality of eccentric strippinggrooves in the pin, the latter being adjustable lengthwise whileremaining in gear to bring any desired one of such grooves beneath thespring blade.

5. A wax pot having, in combination, a receptacle for the wax and astripper comprising a fixed surface and a flat spring' metal memberformed with a portion to cooperate with the fixed surface of thestripper, and a grooved portion bent at an angle to the portioncooperating with the fixed surface for scraping the thread beforepassing through the stripper.

6. A wax pot having, in combination, a receptacle for the wax and astripper comprising a fixed surface and a flat spring metal memberformed with a. portion to cooperate with the fixed surface of .thestripper, a grooved portion bent at an angle to the portion cooperatingwith the fixed surface for scraping the thread before passing throughthe stripper, and another portion bent at an angle to both of the otherportions forming means to attach the spring member to the wax pot.

HARRY E. DOW.

